Smoking element



May 25, 1965 E. c. BUCKINGHAM SMOKING ELEMENT Filed Aug. 12, 1963 20602 C. .BucKwc-wn/w INVENTOR.

ATT RNEYS United States Patent Office 3,185,153 Patented May 25, 1965 3,185,163 SMOKING ELEMENT Edgar C. Buckingham, San Marino, Califi, assignor to Super-Temp Corporation, Santa Fe Springs, Calif, a corporation of California Filed Aug. 12, 1963, Ser. No. 301,260 6 Claims. ((31. Lil-H4) This invention relates to smoking elements, especially smoking pipes, and is particularly concerned with a novel bowl liner and bowl for such pipes.

It is well known that smoking pipes having bowls made or lined of conventional materials require a breakingin smoking period to establish a carbonaceous surface or a coke liner in the bowl of the pipe, for best results. However, even when such a carbonaceous surface is formed Within the bowl, the exterior surface of the pipe bowl becomes quite hot during smoking due to considerable heat transfer through the bowl from the burning tobacco within the bowl. This relatively great heat transfer through the bowl renders the temperature of the burning tobacco non-uniform, and also causes the combustion to cease frequently, requiring frequent relighting of the pipe. Also, in pipe bowls of conventional pipes, moisture undesirably tends to accumulate in the lower portion of the bowl, and also unburned, and partially burned residue formed in the bottom of the bowl often adheres tenaciously to the interior surface of the bowl and is diflicult to remove. Further, materials of which conventional pipe bowls are formed are relatively porous so that mois ture is absorbed by the bowl during combustion of the tobacco. The result is that normally a drying out period is usually required between uses.

Pipe bowls having ordinary carbon liners are known. However, liners of this type do not materially reduce the undesirable heat transfer through the pipe bowl, with its attendant disadvantages noted above, and ordinary carbon liners are porous.

It is an object of the instant invention to provide a smoking element, particularly a bowl or a bowl liner for smoking pipes, which has properties which reduce and preferably avoid substantially all of the above noted disadvantages of conventional smoking pipes having bowls or bowl liners formed of conventional materials.

The above and other objects and advantages of the invention will appear hereinafter.

I have found that a smoking pipe bowl or bowl liner composed of pyrolytic graphite, produces results which are greatly superior to those produced from pipes having bowls formed or lined of conventional materials, and avoids substantially all of the problems described above which are inherent in conventional smoking pipes.

The pyrolytic graphite referred to above is an anisotropic material formed by the high temperature pyrolysis of hydrocarbons, for example, methane, passed over a hot surface at approximately 4,000 F. The carbon atoms are deposited in laminar form on such surface, and deposited so that the direction of high thermal conductivity is always parallel to the deposition surface, or to the plane of the laminate. Thus, the material deposits so that it is always a heat insulator perpendicular to the deposition surface and a good heat conductor parallel to such surface.

Pyrolytic graphite can be produced in the form of a crucible of a desired size and shape so as to form the bowl of a smoking pipe, or to be inserted into and to fit within the bowl of a particular smoking pipe as a liner therefor, such crucible containing an opening adjacent the bottom for connecting with the stem of the pipe. The thickness of such crucible can vary, and can range, for example, from about 0.010 up to about 0.350 inch, and when employed as a bowl liner, the thickness generally ranges from about 0.010 to about 0.100 inch. In order to make a particular shape of pyrolytic graphite crucible, the deposition of the pyrolytic graphite is carried out on the surface of a mandrel of the required shape. This crucible can be attached to the stem of a smoking pipe in any suitable manner to function as the pipe bowl, or it can be incorporated in the bowl of the smoking pipe by any suitable means such as by bonding or by a mechanical fastener to function as a liner for the bowl.

The term bowl element employed herein is intended to denote either the bowl of a smoking pipe or a liner therefor.

The advantages of the pyrolytic graphite bowl element of the invention are essentially due to the unique properties of this material. As deposited in the bowl shape, that as in the shape of a small crucible forming the pipe bowl or as a liner for insertion into the pipe bowl, as previously indicated, the pyrolytic graphite material formed has high thermal conductivity along the bowl surface and is a heat insulator through its thickness. Also, such pyrolytic graphite is a highly dense substantially non-porous material.

Thus, since the pyrolytic graphite bowl element of the invention is an insulator through its thickness, the external surfaces of the pipe bowl will operate at a lower temperature and will be cooler, as compared to the bowl of conventional smoking pipes. Also, the burning tobacco in the pipe is maintained at a more uniform and elevated ten". erature so that the necessity to relight the pipe at frequent intervals is greatly reduced. Since the pyrolytic graphite is a conductor of heat along the inside surface of the bowl element or crucible, heat is maintained within and carried down into the lower bowl area of the pipe and moisture evaporates more readily than in the case of conventional pipes, thus providing a drier and cooler smoke. Further, since the heat is carried more uniformly down into the bowl area, there is considerably less tendency for an unburned or partially burned residue remaining in the bottom of the pipe, and which normally is difficult to remove. 1

It is also particularly noteworthy that since pyrolytic graphite is substantially carbon, it is not necessary to establish a carbonaceous or coke surface on the bowl by a breaking-in smoking period as is normal with pipes made or lined of conventional materials. Further, no moisture is absorbed by the pyrolytic graphite bowl element of the invention during the smoking process, due to the essentially non-porous nature of pyrolytic graphite, thus permitting the pipe to be used extensively without interruption for the drying-out periods between uses necessary with conventional pipes.

The pyrolytic graphite pipe bowl element or crucible of the invention can be made in various shapes and sizes as desired, and such element is thus not limited to any particular smoking pipe design. Moreover, since the pyrolytic graphite bowl element of the invention is a separate element or insert, it can be replaced if either cracked, broken, or worn out without discarding the entire pipe.

The invention will be understood more readily by reference to the description below of certain illustrative embodiments of the invention, taken in connection with the accompanying drawing wherein:

FIG. 1 shows a cross-section of a smoking pipe embodying a bowl liner according to the invention principles;

FIG. 2 shows a section in elevation of the bowl liner of the pipe of FIG. 1;

FIG. 3 is a plan view taken on line 3- -3 of FIG. 2;

FIG. 4 is a cross-section of a smoking p'pe having a bowl constructed according to the invention; and" FIG. 5 is an enlarged detail showing the orientation of the pyrolytic graphite laminae in the bowl or bowl liner of the invention. l

Referring to the drawing, numeral is a pipe according to the invention, which comprises a bowl 112 of a conventional material connected to a hollow stem 14, one side of the bottom of bowl 12 being apertured at 16 for communication of the interior of bowl 12 with the smoke passage 18 in the stem.

Snugly inserted in the pipe bowl 12 is a pyrolytic graphite bowl liner or crucible 20 according to the invention and described above. Such bowl liner is formed by depositing the carbon in the pyrolysis process de-.

scribed above on a suitably shaped mandrel (not shown) so that the laminae are formed substantially parallel to or along the surface of the crucible, as indicated at X in FIG. 5. The bowl liner 20 is maintained fixed in position in the. pipe bowl 12 by any suitable means, as by bonding between the exterior wall of the liner and the adjacent interior wall of the bowl, or by providing a friction fit between the liner and the bowl, or by a suitable mechanical fastening means. One side of the liner adjacent the bottom thereof is provided with a small hole or opening 22 which registers with the aperture 16 in the .bowl 12, to provide communication via aperture 16, between the interior of the liner 20 and the smoke passage 18 in the pipe stem 14. The wall 24 of the liner or crucible 20 can be of a thickness, e.g. about 0.040 inch, and the wall 26 of the pipe bowl 12 can be of conventional thickness or can be made thinner than in conventional pipes, so that the overall thickness of the walls 24 and 26 of the liner and pipe bowl is not substantially greater than the bowl thickness of the conventional smoking pipe.

It will be seen that the pyrolytic graphite crucible 20 is a heat insulator through its thickness in a direction perpendicular to the laminae X, and is a conductor along its inside surface parallel to the laminae X. These properties, together with the high density non-porous characteristics of the pyrolytic graphite, are essentially responsible forthe advantages of the smoking pipe of the invention over conventional smoking pipes having bowls or liners formed of conventional materials, as

' pointed out above.

In FIG. 4 there is shown a modification of the invention in the form of a smoking pipe, indicated at 30, composed of a bowl 32 attached to the hollow stem 34. The bowl 32 is formed of pyrolytic graphite and produced by depositing the carbon in the pyrolysis process previously described, on a. suitably shaped mandrel so that the laminae are formed substantially parallel to the surface of the bowl, as in the case of the bowl liner 20 described above. The bowl 32 has a thickness of the order, of about 0.250 inch and is provided with an aperture 36 in its bottom for communication of the interior of the bowl with the smoke passage 38 in the stem 34. The bowl 32 is mounted on the end of the stem 34 by any suitable fastening means such as spring clips, indicated at 40, so that if desired, the bowl 32 is removable from the pipe stem.

It will be understood, as previously indicated, that the pyrolytic graphite bowl element of the invention, e.g. the bowl liner 20 or the bowl 32, can be formed of any desired shape to fit the design and shape of a particular pipe. Thus, for example, such element can have a cylindn'cal surface as illustrated by bowl liner '20, or a curved surface as illustrated by the pipe bowl 32.

While I have described particular embodiments of my invention for the purpose of illustration, it should be understood that various modifications and adaptations thereof may be made within the spirit of the invention, as set forth in the appended claims.

I claim:

1. A smoking pipe bowl elementhaving an internal surface and comprising a crucible for receiving tobacco and being composed of pyrolytic graphite, said pyrolytic graphite having carbon atoms. oriented in laminae, the laminae of said pyrolytic graphite being oriented substantially parallel to the surface of said crucible, and being apertured adjacent the bottom of the crucible to permit outward passage of tobacco smoke from said crucible.

' 2. A smoking pipe bowl liner having an internal surface and comprising a crucible for receiving tobacco and being composed of pyrolytic graphite, said pyrolytic graphite having carbon atoms oriented in laminae, the laminae of said pyrolytic graphite being oriented substantially parallel to the surface of said crucible, said crucible being adapted to fit within the bowl of a smoking pipe and being apertured adjacent the bottom of the crucible to permit outward passage of tobacco smoke from said crucible.

3. A smoking pipe bowl element having an internal surface, and comprising a crucible for receiving tobacco and being composed of pyrolytic graphite, said pyrolytic graphite having carbon atoms oriented in laminae, the laminae of said pyrolytic graphite being oriented substantially parallel to the surface of said crucible, said crucible having a thickness in the range of about 0.010

to about 0.350 inch, and being apertured adjacent the bottom of the crucible to permit outward passage of tobacco smoke from said crucible.

4. A smoking pipe bowl liner having an internal surface and comprising a crucible for receiving tobacco and being composed of pyrolytic graphite, said pyrolytic graphite having carbon atoms oriented in laminae, the laminae of said pyrolytic graphite being oriented substantially parallel to the surface of said crucible, said crucible having a thickness in the range of about 0.010 to about 0.100 inch, said crucible being adapted to fit within the bowl of a smoking pipe and being apertured adjacent the bot-tom of the crucible to permit outward passage of tobacco smoke from said crucible.

5. A smoking pipe which comprises a tobacco receiv-. ing bowl and a hollow stem, said bowl being connected to one end of said stern, said bowl being aperturred adjacent the bottom thereof to provide communication between said bowl and said hollow stem, a liner in the form of a crucible fitted within said bowl in snug engagement with the wall thereof, said crucible having an-intcrnal surface and composed of pyrolytic graphite, said pyrolytic graphite having carbon atoms oriented in laminae, the laminae of said pyrolytic graphite being oriented substantially parallel to the surface of said crucible, said crucible having an aperture adjacent the bottom thereof in registry with the aperture in said bowl, and providing communication between said crucible and said hollow pipe stem.

6. A smoking pipe which comprises a tobacco receiving bowl and a hollow stern, said bowl being connect e d to one end of said stem, said bowl being apertuired adjacent the bottom thereof to provide communication between said bowl and said hollow stem, said bowl having an internal surface and composed of pyrolytic graphite, said pyrolytic graphite having carbon atoms oriented in laminae, the laminae of said pyrolytic graphite being oriented substantially parallel to the surface of said bowl.

References Cited by the Examiner UNITED STATES PATENTS 723,672 3 /03 Holland. 1,461,126 7/23 Lasure l31220 X 1,862,133 6/32 Bayan 13l226 X 1,897,073 2/33 Pepper 131220 FOREIGN PATENTS 12,604 1915 Great Britain.

OTHER REFERENCES Article: Page 56, Chemical and Engineering News, November 30, 1959.

ABRAHAM G. STONE, Primary Examiner.

JOSEPH S. REICH, Examiner. 

1. A SMOKING PIPE BOWL ELEMENT HAVING AN INTERNAL SURFACE AND COMPRISING A CRUCIBLE FOR RECEIVING TOBACCO AND BEING COMPOSED OF PYROLYTIC GRAPHITE, SAID PYROLYTIC GRAPHITE HAVING CARBON ATOMS ORIENTED IN LAMINAE, THE LAMINAE OF SAID PYROLYTIC GRAPHITE BEING ORIENTED SUBSTANTIALLY PARALLEL TO THE SURFACE OF SAID CRUCIBLE, AND BEING APERTURED ADJACENT THE BOTTOM OF THE CRUCIBLE TO PERMIT OUTWARD PASSAGE OF TOBACCO SMOKE FROM SAID CRUCIBLE. 